Trimming machine



June 16, 1936. Q G, BROSTROM 2,044,054

TRIMMING MACHINE Filed June 27, 1955 2 Sheets-Sheetl .Fun 16, 1936. c. e. BROSTROM TRIMMING MACHINE Filed June 2'7, 1955 2 Sheets-Sheet 2 Patented June 16, 1936 UNITED STATES PATENT OFFICE TRIMMING MACHINE Application June 27, 1933, Serial No. 677,878

22 Claims.

This invention relates to trimming machines and is herein illustrated as embodied in a machine of the type in which a long blade or stripknife is operated with movement lengthwise of its cutting edge to execute a drawcut. A typical example of an operation to which such a machine is Well suited is known in the shoe-making art as toe-trimming. This operation as performed on cement-lasted shoes consists in severing, preferably with a skiving cut, the pleats or folds of upper material that lie on the insoles of the shoes as a result of lasting their toe-ends. Although the quantity of surplus material to be severed is not great in shoes of the type mentioned, never theless, it is desirable to sever the pleats flush with the general plane of the overdrawn and cemented margin of the upper without otherwise severing this margin.

With such an operation in view, an object of the present invention is to provide an improved trimming machine capable of being built at small cost for power-operation or for manual operation, as the purchaser may prefer.

To this end, and in accordance with one feature of the invention, each of the illustrated machines, which embody alternative modifications, comprises a knife-carrier provided with two cooperative knife-holders spaced apart and a knife connecting them, means arranged to engage a lasted shoe and guide it toe-foremost against the cutting edge of the knife, and means by which the carrier is constrained to oscillate in a curved path virtually concentric with respect to the transverse curvature of a shoe-bottom so guided, the operating portion of the knife being curved virtually in accordance with the transverse curvature of the shoe-bottom.

Preferably, and as herein illustrated, the knifecarrier is arranged to oscillate about an axis and the knife-holders are constructed and arranged to curve a normally fiat but flexible strip-knife in accordance with the curvature above mentioned. Nevertheless, the illustrated machines are also provided with adjustable knife-guides by which the curvature of the cutting portion of the knife may be regulated, eliminated, or even reversed, consistently with the requirement of various shapes and conditions of work. For example, the best results may be obtained in some shoes by trimming more deeply in the middle than at the sides.

In both modifications herein illustrated the work-guiding means are manually movable to lead a work-piece to the trimming knife, but in one of them power-operated mechanism is provided to operate the knife-carrier, whereas, in the other the knife-carrier is intended to be operated manually. Moreover, in the latter, the workguiding means and the knife-carrier are interconnected by mechanism arranged to communithe axis about which it oscillates is below the 15 knife which, for the convenience of the operator, is preferably located at a level about waisthigh. Moreover, the axis of oscillation is preferably located at a level not far above the floorlevel, to the end that the effective radial length of the knife-carrier may be sufficient to provide for considerable travel of the knife without requiring the knife-carrier to move too far from its median position of balance.

Also, the carrier that constitutes an element 5 of the work-guiding means is preferably an inverted pendulum, the axis of which is located not far above the floor-level, for the reason above explained in reference to the knife-carrier, and

for the additional reason that it is desirable to V avoid appreciable rocking of a shoe guided thereby.

The two inverted pendulous carriers may therefore be most advantageously mounted, as herein illustrated, on the steadiest part of a machine frame, that is, the base from which a column rises to support other necessary elements of the assemblage. Moreover, with regard to the type designed for manual operation, the described mounting of the knife-carrier provides for equipping that carrier with an operating treadle in rigid relation thereto.

The invention also provides an improved combination of elements designed to utilize a relatively short portion of a long flexible strip-knife the major portion of which may be stored in coils and be unwound little by little from one coil as sharp portions are needed for operation, and wound up in another coil as the used portions become dulled, to the end that substantial economies may be effected in the manufacture and in the sharpening of knives and in the replacement of dull knives with sharp ones. In some respects this aspect of the invention is developed to afford advantages not provided for in the construction illustrated in my copending application Serial No. 672,628 filed May 24, 1933.

Referring to the drawings,

Fig. 1 is a top-plan view of a trimming machine embodying the invention in a construction designed for manual operation;

Fig. 2 is a front elevation thereof;

Fig. 3 is a view partly in side elevation and partly in vertical section showing the trimming knife, the toe portion of a shoe and means for controlling presentation of the shoe to the knife;

Fig. 4 is a side elevation, partly broken away, of a machine in which the principles of the invention are embodied in a construction designed to be operated by factory power;

Fig. 5 is a front elevation of the machine represented in Fig. 4;

Fig. 6 is a side elevation, partly in vertical section, of the work-guiding or controlling means included in Fig. 3;

Fig. 7 is a horizontal section through the structure intersected by line V1'IVII of Fig. 6; and

Fig. 8 is a front elevation of certain parts included in Fig. 6.

In both types of machines herein illustrated an intermediate portion of a normally flat but flexible strip-knife I0 is clamped to and carried by two arms ll of an inverted pendulous carrier l2 the lower end of which is provided with a socket for the reception of a horizontal pivotpin l3 mounted in the base M of the machine frame. The axis of the pin I3 is arranged to provide for oscillation of the knife-carrier lengthwise of the knife I. The upper ends of the arms II are spaced apart to provide an unobstructed space between them for a shoe and shoe-guiding means, and each arm is provided with a knife-holder comprising a clamping boss IS in which a channel is formed to receive the knife l0 and a movable clamping plate IS. The upwardly projecting confronting cheeks of the bosses I5 are bored to provide bearings for pivotpins IT on which finger-levers I8 are mounted. Each lever I8 has a cam-shaped hub formed to apply clamping pressure to the underlying plate l6 and thus secure the strip-knife ID to the knife-carrier. These details of construction provide for shifting the strip-knife lengthwise with respect to its carrier whenever the operating portion of the knife connecting the knife-holders becomes dull and it is desired to bring a sharp portion of the knife into the operating range between the knife-holders.

As shown in Figs. 2 and 5, the knife-clamping devices are angularly related to each other and arranged to bow the intermediate portion of the knife upwardly to maintain it in an abnormal state of arcuate curvature concentric to the axis of the pivot-pin 13 about which the knife moves in operation.

Figs. 1 and 2 include means for supporting and constraining coiled portions 20 and 2| of the strip-knife, in one of which the sharpened portion of the knife may be stored and in the other of which the portion dulled by use may be stored. The choice of locations of the sharp portion and the dull portion is optional but for purposes of description it will be assumed that the sharpened portion is in the coil 20 and that the dulled portion is in the coil 2!. Each of these coils is supported by a pair of flanged spools 22 and constrained against uncoiling by another pair of flanged spools 23. All the spools are preferably made of wood to avoid dulling the cutting edge of the knife. The supporting spools 22 are rotatably mounted on spindles 24 adjustably clamped to supporting brackets 25 in which slots 26 are formed to receive the spindles and to provide for adjusting the spools toward and from each other in accordance with changes that occur in the diameters of the coils. The spools 23 are likewise adjustably mounted on a slotted bar 21 from which an intermediate stem 28 projects downwardly and is arranged to slide in a boss 29 formed on the bracket 25. Thus, as one coil increases and the other decreases in diameter one of the coil-constraining devices expands and the other contracts automatically under the force of gravity. If supplemental constraining force is needed annular weights may be placed on the upwardly projecting stems 28' of the bars 21.

Whenever an operating portion of the stripknife becomes dull, the operator may readily replace it with a sharp portion in the following manner. First he will turn the handles of the clamping devices l8 to release the clamping plates l6; he will then draw a fresh length of the knife from the coil containing the sharpened portion; then feed the knife lengthwise to bring a sharp portion between the clamping devices; tighten the clamping members l8 to secure the knife in the new position; and rotate the coils 28 and 2| as may be necessary to take up surplus slack between them and the knife-carrier but still leaving sufiicient slack in the outlying portions of the knife to provide for the to-and-fro motions of the knife-carrier.

When substantially the entire length of the strip-knife has been dulled by use and has been gradually taken up in the form of a coil, this coil may be quickly detached from the machine and placed in a container for removal to a sharpening apparatus, the holders to which the spools 23 are attached being readily removable from their sockets 29 without the use of any tool.

The supporting brackets 25 are affixed by bolts 30 to an overhanging portion 3! of the frame that projects forwardly from the top of a column 32. This portion 3| of the frame projects into the space between the knife-clamping devices %5 and also supports two freely rotatable knife-guiding rolls 32 that underlie and engage the operating portion of the knife It. The rear ends of these rolls are provided with radially projecting flanges 33 arranged to engage the rear edge of the knife and thus brace the knife against the force with which the work is thrust against the front edge which is the cutting edge of the knife. The rolls 32 are arranged in tangent relation to the are or curve of the operating portion of the knife and are spaced one from the other far enough to permit the forepart of a shoe and suitable shoeguiding members to enter the space between them without encountering interference.

Midway between the rolls 32 the knife extends under but in engagement with a fixed guide 34 by which it is braced against upward displacement by the work. The guide 34 is provided with an upwardly extending shank or stem 35 which is mortised into, and vertically adjustable in, a grooved portion of a fixed bracket 36. A clamping bolt 3'! extends through a vertical slot in the shank 35 and has screw-threaded connection with the bracket 36. The knife-guide 34 may therefore be adjusted to various levels, and by this means the curvature of the operating portion of the knife may be regulated or eliminated, or it may even be reversed by depressing the knife below the level of the tops of the guide-rolls 32.

The bracket 35 is seated upon a horizontal surface of the portion 3.! of the frame and is afllxed thereto by a clamping bolt 38. A. slot 39 formed in the bracket to receive the bolt 38 provides for: adjusting the bracket to the front or rear as may be necessary to place the guide .34 in re ister with the knife.

Presentation of a shoe to the trimming knife I is controlled by a manually movable work-guidin unit comprising a combination of adjustable work-engagin m mbers mounted on an inverted pendulous carrier .40 and arranged to move to the front and rear in th space between the knifeholders I5. The lower end of this carrier is mounted on a pivot-pin, 4| the axis of which is transversely related to that of the pivot-pin 43 to constrain the shoe-guiding members to movement crosswise of the trimmingknife The upper end of the carrier 40 is bored downwardly to nrovide a socket for a substantially vertical post 42 and is divided by a kerf so that it may be contracted by a bolt 43 to clamp the post. A block 44 is aflixed to the upper end. of the post by a screw 45, the head of which is, effective to clamp a plate 46 mortised into the block. The clamping screw extends through a vertical slot 4! in the plate (Fig. 8), this detail affording vertical ad- J'ustment of the plate with respect to the block. A trimming-gage comprising a thin horizontal tongue 48 carried by the plate 46 is arranged to overlap and engage the cement-lasted margin of the upper 49 of a lasted shoe, as represented in Fig. 3, in which the pleats or folds to be severed are indicated at 50, the insole at and a last at 52. The tongue 48 and the plate 46 are provided with cooperative dovetail formations by which they may be rigidly connected, the plate being provided with a kerf 53 (Fig. 8) and with a screw 54 by which it may be contracted to clamp the tongue. A pad 55 of suitable cushioning material, such as felt, is carried by the block 44 to provide an abutment against which the toe of a shoe may be thrust to impart operating movement to the carrier 40. This pad is preferably mortised into dovetail ribs 56 formed on the block 44 (see Fig. 7). A. hole 51 extending through the pad 55 provides a socket into which the head of the screw 45 is sunk to avoid marring the toes of the shoes.

The upper end of the carrier 40 is also pro vided with a substantially vertical post 59. As shown in Figs. 1 and 2 this post extends through a split boss 58 formed on the carrier 40. A screw 60 is arranged to contract the boss 58 to clamp the post in various positions of adjustment, the post being angularly adjustable about its axis and adjustable lengthwise of its axis for height. The upper portion of the post is formed to overhang the forepart of a shoe when the toe of the shoe is placed against the pad 55 and the tongue 48 as shown in Fig. 3. A cross-bar 6| affixed to the post 59 is arranged to extend across the forepart of a shoe and engage the opposite margins of the upper material that have been secured to the bottom of the insole with cement or other means. When the upturned bottom of a shoe is held against the tongue 48 and the crossbar BI as shown in Fig. 4, the shoe is constrained skive the. pleats or folds 50 of the shoe with a draw-cut.

:lihe construction shown in Figs- 1. and 2 is degned to utilize. the manual efforts of the operator to operate the trimming knife In with movement lengthwise of its cutting edge. For this purpose, the work-guiding carrier 40 and the knife-carrier are interconnected with a train of mechanism by which motion of either carrier is communicated 'to the other, the connecting mechanism including a bell-crank lever 62, a. link 53 formin connection between one arm of the lever and the carrier 40, and a link 64 forming connection between the other arm of the lever and one arm I l of the knife-carrier. The operating connections between each of the links 63 and 64 and the elements connected by them comprise ball-and-socket joints 19, four in all. The fulcrum of the bell-crank lever 62 is provided by a pivot-pin 55 that extends through a pair of brackets 66 between which the lever is arranged, the brackets being formed on the column 52. This train .of mechanismis so arranged that when the work-guiding carrier 40 is moved to the rear the trimming knife will be movedfrom right to left across the shoe. If desired the knife-carrier may be provided with a treadle 61 by which a supplemental manual force may be applied to assist the operators hands in imparting operating movement to the carriers. Preferably the knife-carrier is braced and its to-and-fro movements are guided by a forked bracket 68 (Fig. 2) affixed to the column 32. This bracket may also serve as an abutment to arrest the carriers at both limits of their range of movement one of which may be regulated by an adjustable screw 59 threaded in the carrier 40 and arranged to abut against the bracket when the carrier 40 reaches the terminal limit of its movement from front to rear.

Since the. trimming knife'operates with a drawout crosswise of a shoe it exerts a frictional drag that tends to displace the shoe sidewise. In a machine of the type shown in Figs. 1 and 2 the knife operates only when moving from right to left. Accordingly, the carrier 40 in that machine is provided with a work-guiding abutment l3 arranged to brace the forepart of the shoe against such movement. This abutment may pass under and clear the knife l0. As shown it is made of a round rod bent to right-angular form, one arm thereof being arranged in a boss H and secured therein by a set-screw 12.

When operating a machine of the type shown in Figs. 1 and 2, the operator may hook the thumb or forefinger of his left hand around the workguiding member and support the forepart of the shoe in the upturned palm of that hand to insure firm engagement of the bottom of the shoe with the tongue 48 and the cross-bar 5!, meanwhile grasping the heel-end of the shoe in the palm of his right hand with which he will thrust the shoe against the trimming knife. Some operators may prefer to furnish all the necessary operating force with their hands not only to move the work-guiding carrier 40 to the rear but also to swing the knife carrier from right to left, while others may prefer to furnish some of the operating force with the left foot as by depressing the treadle 61 while thrusting the shoe to the rear. In either case, a single stroke of the knife is sufiicient to sever all the pleats or folds 55 that have been formed at the toe of the shoe. The carriers may be returned to their initial positions by pulling forward the work-guiding member IE3 with the thumb or forefinger of the left hand.

The construction shown in Figs. 4 and 5 differs from that shown in Figs. 1 and 2 chiefly in that it is designed to utilize factory power for operating the knife-carrier. Since the knife may operate when moving in opposite directions, the workguiding carrier is provided with two work-guiding abutments (Fig. 5) arranged to brace the forepart of a shoe against the frictional drag of the trimming knife in both directions. As shown in Fig. 4, the column 32 of the frame is provided with bearings 13 for a horizontal shaft 14. A crank-pin 15 carried by this shaft is provided with a square sleeve 16 arranged to operate in a slot 11 formed in the knife-carrier l2 in radial relation to the pivot-pin [3. A tight pulley 18 and a loose pulley 19 are arranged on the shaft 14 to receive a driving belt (not shown). Adjacent to the junction of the arms II the knife-carrier is braced and guided by a grooved bracket 80 affixed to the column 32. This bracket stands in the path of the adjustable stop-screw 69 carried by the work-guiding carrier 40 and serves to arrest this carrier at the terminal limit of its movement from'front to rear. The forward travel of the carrier 40 is arrested by an abutment 8| formed on the base l4 and arranged to be engaged by a boss 82 formed on the carrier. A torsion spring 83 is arranged to maintain the carrier 40 normally in its forward position.

The work-guiding carrier 40 shown in Figs. 4 and 5 is designed to provide four kinds of adjustment for the post 59 in consequence of mounting the post in an intermediate clamping member 85 provided with a split clamping socket and a clamping bolt 86 and with a cylindrical shank or stem 81. This stem is arranged in a split clamping socket 88 formed in the carrier 40 and provided with a clamping bolt 89. This intermediate member may be adjusted lengthwise of its stem 81 and may be turned in its socket 88, while the post 59 may be adjusted up and down and may be turned in its socket 85.

The manner of operating a machine of the type shown inFigs. 4 and 5 need not differ essentially from that for operating a machine of the type shown in Figs. 1 and 2, although in the type designed to utilize factory power for operating the knife-carrier no treadle is provided since a relatively slight manual effort suffices to move the work-guiding unit from front to rear. In a machine of this type no manual effort is required to return the work-guiding unit to its initial position, the spring 83 being sufiicient for that purpose.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A trimming machine comprising a carrier provided with two cooperative knife-holders spaced apart and a knife connecting them, means arranged to engage a lasted shoe and guide it toe-foremost against the cutting edge of said knife, and means by which said carrier is constrained to oscillate in a curved path virtually concentric with respect to the transverse curvature of a shoe-bottom so guided, the operating portion of said knife being curved virtually in accordance with said transverse curvature of the shoe-bottom.

2. A trimming machine comprising work-guiding means constrained to travel to and fro to guide a lasted shoe in a certain path by engagement with its bottom surface, a reciprocatory carrier provided with two spaced arms and a trimming knife connecting them, said carrier and.

said knife forming a closed loop that encircles said path, and means arranged to reciprocate said carrier to operate the knife.

3. A trimming machine comprising a reciprocatory carrier provided with two cooperative knife-holders spaced apart and a knife connecting them, means arranged to reciprocate said carrier lengthwise of said knife, a movable Workguiding unit provided with a trimming gage arranged to engage the bottom of a lasted shoe at the toe-end thereof, and means by which said unit is constrained to guide the toe-end between said knife-holders.

4. A trimming machine comprising a carrier arranged to oscillate about an axis, the carrier having two arms spaced apart to provide an unobstructed space between them, an arcuate knife carried by and connecting the outer ends of said arms, means arranged to oscillate said carrier about said axis, and shoe-guiding means constrained to move and operate in the space bounded by said arms and said knife to control presentation of a shoe to the latter.

5. A trimming machine comprising a knifeca-rrier arranged to oscillate about an axis and having two arms spaced apart to provide an unobstructed space between them for a shoe and shoe-guiding means, said arms being provided with angularly related knife-holders arranged to maintain a normally fiat but flexible strip-knife in a state of abnormal arcuate curvature virtually in concentric relation to said axis, a flexible strip-knife carried by said knife-holders, and shoe-guiding means movable in said space to control presentation of a shoe to said knife.

6. A trimming machine comprising a reciprocatory and manually operable knife-carrier having two knife-holders spaced apart to provide an unobstructed space between them for a shoe and shoe-guiding means, a knife carried by and connecting said knife-holders, shoe-guiding means constrained to move into said space to control presentation of a shoe to said knife, and a treadle by which the knife-carrier may be operated.

'7. A trimming machine comprising a knifecarrier and shoe-guiding means pivotally mounted to be oscillated about axes transversely related to each other, said knife-carrier having two spaced knife-holders between which said shoeguiding means and a shoe are movable, and a skiving knife carried by and connecting said knife-holders.

8. A trimming machine comprising a movably mounted trimming cutter, manually movable means arranged to guide a work-piece against said cutter, and means arranged to communicate motion from said work-guiding means to said cutter to operate it.

9. A trimming machine comprising a movably mounted skiving knife, manually movable means arranged to guide a work-piece toward and past the cutting edge of said knife, and means arranged to communicate motion from said workguiding means to said knife to operate the latter with motion lengthwise of its cutting edge.

10. A trimming machine comprising a skiving knife and a carrier by which it is mounted to operate with movement lengthwise of its cutting edge, manually movable means arranged to guide a work-piece toward and against said cutting edge, means arranged to communicate motion from said work-guiding means to said carrier to operate the knife, and a treadle arranged to communicate a supplemental operating force from the operator's foot to said carrier.

11. A trimming machine comprising a skiving knife and a carrier by which it is mounted to operate with movement lengthwise of its cutting edge, a treadle arranged to operate said carrier, movable means arranged to guide a work-piece toward and against said cutting edge, and means arranged to communicate operating motion from said carrier to said work-guiding means and reverse motion from said work-guiding means to said carrier.

12. A trimming machine comprising a knifecarrier and manually movable work-guiding means arranged to be oscillated about transversely related axes, a trimming knife mounted on said carrier, and means arranged to communicate toand-fro movements of said work-guiding means to said carrier to operate the trimming knife in one direction and to retract it to an initial position.

13. A trimming machine comprising an inverted pendulous knife-carrier having two upwardly extending arms and an upwardly bowed stripknife connecting them, work-guiding means arranged to be moved under said knife and between said arms, and means arranged to oscillate said knife-carrier about an axis virtually at the center of curvature of said knife.

14. A trimming machine comprising an inverted pendulous knife-carrier having two upwardly extending arms and an upwardly bowed stripknife connecting them, an operating treadle carried by said carrier, and work-guiding means arranged to be moved in the space bounded by said arms and said knife to control presentation of a work-piece to the knife.

15. A trimming machine comprising an inverted pendulous knife-carrier and a skiving knife carried thereby above its axis of oscillation, manually movable work-guiding means arranged to control presentation of a work-piece to said knife, and means arranged to communicate motion from said work-guiding means to said knife-carrier to operate it.

16. A trimming machine comprising two inverted pendulous carriers arranged to be oscillated about transversely related axes, one of said carriers having two upwardly extending arms and an upwardly bowed strip-knife connecting them, and the other one of said carriers having work-engaging means arranged to guide a work-piece into the space bounded by said arms and said knife, and means arranged to operate said knife-carrier with to-and-fro motions about its axis.

17. A trimming machine comprising two inverted pendulous carriers arranged to be oscillated about transversely related axes, one of said carriers having two upwardly extending arms and an upwardly bowed strip-knife connecting them, and the other one of said carriers having workengaging means arranged to guide a work-piece into the space bounded by said arms and said knife, and means arranged to communicate motions of one of said carriers to the other.

18. A trimming machine comprising a reciprocatory carrier, a'strip-knife carried thereby, the cutting edge of said knife extending lengthwise of its path of movement, a treadle arranged to move said carrier in one direction, work-guiding means arranged to move to and fro crosswise of said path, and means arranged to communicate to-and-fro motions of said carrier to said workguiding means and vice versa, whereby the workguiding means is rendered effective to move said knife-carrier in its other direction.

19. A trimming machine comprising a skiving knife, a carrier by which it is constrained to move lengthwise of its cutting edge, work-guiding means constrained to move crosswise of said cutting edge to control presentation of a work-piece thereto, said work-guiding means being provided with an abutment by which advancing movement of the work-piece is communicated thereto, and mechanism by which advancing movement of said workguiding means is caused to operate said knifecarrier.

20. A trimming machine comprising a frame including a base and an upstanding column provided with an overhanging part extending forwardly therefrom, an inverted pendulous knifecarrier pivotally mounted on said base, a stripknife carried by said carrier, means mounted on said overhanging part to brace an intermediate portion of the knife against the force of a work piece moved against the knife, means arranged to impart reciprocatory operating movement to said knife-carrier, and means arranged to guide a work-piece to said knife.

21. A trimming machine comprising two stationary coil-supporting devices spaced apart and a flexible strip-knife two separate portions of which are coiled and supported by said devices respectively, the intermediate portion of said knife being slack, and reciprocatory knife-operating means provided with two knife-clamping devices spaced apart to provide an unobstructed operating space between them and arranged to clamp said intermediate portion at separate points.

22. A trimming machine comprising two expansible coil-constraining devices spaced apart and arranged to apply radial compressing force against the peripheries of two coiled portions of a flexible strip-knife having an intermediate coilconnecting portion, and knife-operating mechanism including movable clamping means arranged to clamp and operate said intermediate portion of the knife.

CHARLES G. BROSTROM. 

